19911668503 has 2 divisors, whose sum is σ = 19911668504. Its totient is φ = 19911668502.

The previous prime is 19911668473. The next prime is 19911668593. The reversal of 19911668503 is 30586611991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19911668503 - 2¹³ = 19911660311 is a prime.

It is a super-2 number, since 2×19911668503² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19911668593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9955834251 + 9955834252.

It is an arithmetic number, because the mean of its divisors is an integer number (9955834252).

Almost surely, 2^19911668503 is an apocalyptic number.

19911668503 is a deficient number, since it is larger than the sum of its proper divisors (1).

19911668503 is an equidigital number, since it uses as much as digits as its factorization.

19911668503 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 349920, while the sum is 49.

The spelling of 19911668503 in words is "nineteen billion, nine hundred eleven million, six hundred sixty-eight thousand, five hundred three".